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A134623
a(n) = the n-th positive integer which is missing from A134624.
1
2, 3, 5, 7, 8, 9, 11, 12, 13, 15, 17, 19, 20, 21, 23, 25, 28, 29, 30, 31, 32, 33, 35, 36, 37, 39, 41, 43, 44, 45, 47, 48, 49, 51, 53, 54, 55, 56, 57, 59, 61, 63, 65, 67, 68, 69, 71, 73, 76, 77, 78, 79, 80, 81, 83, 84, 85, 87, 89, 91, 92, 93, 95, 97, 100, 101, 102
OFFSET
1,1
COMMENTS
A134624(1) = 1. A134624(n) is the smallest integer which is > A134624(n-1) and is different from and not coprime to a(n-1). [corrected by Michel Marcus, Sep 06 2019]
PROG
(PARI) missing(n, v) = {my(nb = 0, k = 1, s = Set(v), ok = 0); while(!ok, if (! setsearch(s, k), nb++); ok = (nb == n); if (!ok, k++); ); k; }
nextt(start, cop) = {my(k = max(start+1, cop+1)); while(gcd(k, cop) == 1, k++); k; }
list3(nn) = {my(v3 = vector(nn), v4 = vector(nn)); v4[1] = 1; for (n=1, nn, v3[n] = missing(n, v4); if (n+1 > nn, break); v4[n+1] = nextt(v4[n], v3[n]); ); v3} \\ Michel Marcus, Sep 06 2019
CROSSREFS
Sequence in context: A274688 A053661 A171944 * A228373 A156271 A186513
KEYWORD
nonn
AUTHOR
Leroy Quet, Nov 04 2007
EXTENSIONS
More terms from Michel Marcus, Sep 06 2019
STATUS
approved